Lubricator



Jan 19, 1943- c. A. NORGREN ETAL 2,308,773

LUBRICATOR Filed June 9, 1941 Cdr/ A. Norgren d/fo/ Patented Jan. 19, 1943 LUBBICATOB Carl A. Nogren, Denver, Colo., and Per Gunnar4 almgren, Philadelphia,

Application June 9, 1941, Serial No. 397,286

4 Claims. (Cl. 184-55) This invention relates to improvements in lubricators for pneumatically operated devices or the like, particularly lubricators of the type disclosed in United States Patent No. 1,782,741, issued November 25, 1930, and United States Patent No. 2,223,700, issued December 3, 1940.

Lubricators of this type are connected into the compressed air line that supplies the pneumatic device. Another important use for such lubricators is to conduct a mixture of oil and air to lubricate bearings or any moving part, regardless of whether the device is pneumatically operated or not.

Such lubricators make use of the venturi principle whereby a moving ilow of air draws oil from a reservoir into the air stream, whereby it is conducted to the parts to be lubricated.

Lubricators of this character are in extensive use and it has been found that where there is a considerable pressure differential between the high pressure side and the low pressure side of the venturi, accurate automatic metering of the oil becomes diilicult with conventional needle valve control.

Furthermore, there may be wide variations in the velocity of the air passing through the venturi, resulting in fluctuations of the differential in pressure on opposite sides of the venturi, causingerratic and widely varying delivery of the oil.

A typical example of operating conditions that cause a relatively large pressure differential across the venturi is where a lubricator of this type is used to blow a mixture of oil and air into the bearings of a high speed grinding spindle or the like. In such an installation, the air blows through the bearings and out to the atmosphere, serving the -trple useful purpose of lubricating the bearings, tending to cool the bearings and the moving parts, and blowing dirt and other foreign matter constantly away from the bearings. This relatively free flow of air even at low pressures, tends to create an excessive Venturi action which makes metering of the oil diiiicult with conventional lubricators of this type.

An erratic fluctuation of the air velocity and hence variation of air pressure differentials across the venturi may be caused where a lubricator of this character is connected into the compressed air line supplying a variable speed air motor, for instance.

Ordinarily, the flow of oil into the venturi has been governed by positioning of a needle valve or the like, but under the aforesaid circumstances. it may be necessary to so nearly close the needle valve resulting in a single annular oilpassing aperture at the valve, that is so extremely limited in area thatsurface tension in the oil. the presence of foreign matter in the oil or other factors may lead to a variable oil delivery with possible stoppage of the ow altogether. It is manifest that the unpredictable results of these varying conditions are undesirable and the general object of the present improvement in this art is to provide practical means for overcoming these diilculties.

More specifically, an object of the present invention is to provide in a lubricator of this type, a body of porous or fibrous material through which the-oil must pass and which for physical reasons of resistance due to labyrinth action, capillarity. surface tension, friction and the like, contributes materially to governing and regulating the flow of oil or other uid, while still maintaining a relatively great fluid-passing area.

Another object is to provide in such a device, a mass of porous or brous material that is compressible, together with cooperative means for selectively compressing it, whereby the minute conductive passages within the porous or iibrous body may selectively be regulated, thereby definitely governing the amount of oil or other fluid passing therethrough according to requirements.

Still another object is to provide in a pneumatic lubricator, means for cleaning and filtering the oil as it is fed into the flow of air.

Other objects and advantages reside in details of design and construction which will be more fully disclosed in the following description and in the drawing wherein like parts have been similarly designated and in which:

Figure 1 is a front elevation partially in section, of a lubricator built according to the present inventive concept; and

Figure 2 is a fragmentary sectional view taken along the line 2-2 of Figure 1 and drawn on a larger scale.

In order to disclose an operative reduction to practice of the present invention, the accompanying drawing will be described in some particularity. However, the instant example is merely typical and should not be construed to express or to imply any limitation to the invention, the scope of which is, in reality, measured by the appended claims.

First referring to Figure 1, reference character 5 denotes a bowl which, in the instant example, is made of transparent plastic material and which is for the purpose ofholding a supply of oil. The bowl or reservoir 5 is topped by a closure l through which is proided an air conductive passage 1 inclusive of aVenturi portion l of re-r.

duced cross section.

On the high pressure side of the venturi, a small passage connects the mainrair passage with the interior of the bowl or reservoir 5 to maintain air pressure therein. The direction of flow of air is indicated by arrow III. Y

A relatively small oil .passage I2 connects into the venturi I and alsoiinto the interior of a sightfeed glass I3 that is preferably in an erect position as illustrated.

Extending downwardly into the interiorof the sight feed glass Il is anoil drip nozzle I4 in which is a body of porous or fibrous material I5 immediately above which is a washer or disk I6` having a projection that is normally in contact with the upper portion of the material I5.`

A regulating set screw I1 is provided with a knurled head Il and is positioned to cooperate with the disk I6 whereby said disk can be urged toward the porous or fibrous material I5 to compress selectively said material, thereby regulatasosivvs of drops per minute that will.y be fedby the 4 pass through the material I5,'i. el, the number lubricator. It is manifest that according to theinstant example, oil is owed downwardly upon the mass I of porous or fibrous material II'adjacent the periphery thereof, whence it penetrates through the maze of pores kand openings therein toward the central opening vof the nozz1e,sub;|e,c`t to a zone of pressure or compression within the material n I5, thatl may be selectively controlled by'means of hand-screw |1I5 acting upon disk I5, which ing its oil-conductive capacity. A packing gland I9 is provided around the screw I1.

An oil conductive tube 20 extends into the oil bowl or reservoir 5 and, as best illustrated in Figure 2, connects with an oil passage 2I that in turn connects with a closed chamber 22 immediately above the disk I6. The passage 2| is provided in a column that ispart of the closure `5 and thathelps to support the sight feedjglass I3 and the elements positioned thereabove, the

details of which are well and clearly illustrated in Figure 2. y l

It is manifest that as a flow of air under pressure passes in theY direction of arrow III through conductor 1 and venturi 5, oil or other fluid will be drawn from bowl or reservoir 5 upward through tube 20 and passage 2l into chamber 22, Disk I6 is positioned in a suitable guiding recess in the upper portion of the nozzle element I4, but does not t oil-tight therein, butV rather permits oil to flow downwardly around its periphery and onto the mass of porous or fibrous.

material I5. K

As the oil penetrates into and through the maze of small pores and passages within the `mass of material, it is filtered and cleaned of any solid foreign matter -that may be present therein. The oil will pass slowly through'the porous or fibrous material I5 and down through the lower open end of the drip nozzle I4, in the form of drops visible through the sight feed glass I3, Y

thence through the passage I2 and'into the air stream flowing through the venturi 8. In the air stream the oil will be'broken up into fine particles or atomized, and this mixture will be conducted to the parts to be lubricated.

'I'he mass of porous orbrous material I5 contributes to retarding', governing and dependably controlling the flow of oil through the device. It has been found that by virtue of this improvement, unpredictable flow performance due to erratic air velocities or relatively high air pressure drops across the venturi, may be dependably controlled and rendered automatic throughout in-V definite periods of time. j Furthermore, by regulating the pressure of the disk I6 by `means of the hand-screw I1-Il, upon the mass of porous or fibrous material I5, the conductive capacity of the material I5 can be regulated. In other words, the position of the screw I1 readily and dependably may be used to govern the amount of oil or other fluid that will in turn is positioned toact upon porous or fibrous material` I5.

It will be noted thatl immediately belowthe the mass of `material I5 is a central `funnel-like opening Ilavk same time, a zonev of compression will 'be estabf lished thatdependablywill govern and regulate the ilow of oil .through vthe material I5 toward the central opening I la and thence to the normal drip passage IIb through the nozzle I4. A

highlyA satisfactory material of which'to make the component mass I 5 is one or more disks 'or layers of felt; However, the invention is not limited to any specific material since other porous or fibrous bodies having the disclosed characteristics may be used.

It has been stated hereinbefore that the body I5 of porous or fibrous material somewhat re-v tards the now of oil. While this is true, nevertheless the suction effect produced by the pres-A sure differential across the venturi, i. e., the difference in pressure between the interior of the bowl 5 and the interior oi the venturi 8 adjacent the passage I2, will readily act through the porous or fibrous material I5 to drawoil 'up into chamber 22, whence its downward ilow,` will be regulated and stabilized due to thefactos of conductive capacity,`viscosity and/frictiomas the oil passes through the many small pores and openings-in the material I 5', f

It is manifest that different `operating condi# tions willrequire different settings of the con-` trol screw I1-I8,' and the otherfactors in the lubricator are designed and coordinated to sup-` ply the maximum of lubricant that maybe required, and are subject to the position of screw I1-I 8. When the regulating screw I1`I5y hasv once been set to supply the optimum number of drops of oil per "minute, then the oil feedwill be constant and dependable and notsubjectto theerratic action andy trouble under` circumstances hereinbefore `pointed out. `This is trueV throughout a period` of operationv of thermachine being serviced bythe lubricator and itis also true that the setting will remain dependable between periods of operation without f urther attention so that even though afmachinev 1 maybe shut downfor a .considerable period of time, nevertheless'the lubricator will immediate? j ly start functioningrproperly when operationlof themachine serviced therebyfislresumed.

In the following claims, the term reservoir for oil maybe considered as element 5, the air f flow passage element 1 4, and the oil-conducasosms ponent l5, the disk having a boss-like projection is member I6, and the means for acting upon the disk is element i'l-i8.

What we claim and desire to secure by Letters Patent is:

l. In a sight ,feed lubricator of the character disclosed inclusive of a reservoir for oil, a Venturi air flow passage, and an oil conductive passageway leading from said reservoir to said air passage, the improvement which comprises a body of porous material positioned in said oil passageway and llng the cross section thereof, and means inclusive of a non-porous disk positioned to act upon said porous material, and a screw in .thrust engagement with the disk for selectively compressing said body of brous material.

2. In a sight feed lubricator of the character .disclosed inclusive of a reservoir for oil, a Venturi air ow passage, and an oil conductive passageway leading from said reservoir to said air passage, the improvement which comprises a disk of porous material positioned in said oil passageway and filling the cross section thereof, the cross sectional area of .the passageway on one side of the body oi.' porous material being less than that of the passageway on the other side of the material thus forming a shoulder upon which said material bears, a nonporous disk positioned in the larger diameter portion of .the passageway adjacent said porous material and having a boss-like projection extending toward said material for contact therewith, the perimeter of the disk permitting ilow oi oil therepast, and means for urging .the disk toward the porous material whereby the latter may be selectively compressed.

3. In a sight feed lubricator of the character disclosed inclusive of a reservoir for oil, a venturi air flow passage, and an oil conductive passageway leading from said reservoir to said air passage, the improvement which comprises a disk of porous material positioned in said oil passageway and illling the cross section thereof, the cross sectional area of the passageway on one side oi.' the body oi.' porous material bemeans for urging the disk toward the porous material whereby a central zone of compression may be selectively established in said body oi' porous material thereby controlling its fluid-conducting capacity.

4. A lubricator of the character disclosed comprising a bowl for oil, a Venturi air passage positioned thereabove and associated therewith, an oil conductive passageway leading from the interior of said bowl to a position above said air passage and adjacent thereto, a nomle having a central vertically-extending oil hole fitted into said oil passageway, a disk of porous material positioned in the oil passageway and covering the upper end of the oil hole in said nozzle, means for compressing saidporous material .to establish a zone of compression therein in axial alinement with the hole in the nomle, and a sight i'eed glass surrounding the lower end of said nozzle and in conductive communication with said Venturi air passage.

CARL A. NORGREN.. PER GUNNAR PALMGREN. 

